Electric fuse



tat-ant WILEELM ESCI-TIBACH AND WALTER FRIEDERICH, OF TROISDORF, NEAR COLOGNE-ON- THE-RHINE, GERMANY ELECTRIC FUSE No Drawing. Application filed. November 10, 1927, Serial No. 232,462, and in Germany November 23, 1926.

The composition hitherto used for electric ing of neutral polybasic lead picrate adapted ignition pellets contain at the bottom copper to ignite said composltion.

acetylide and above it a mixture of potassium In testimony whereof We have signed our chlorate and pulverized carbon. hen this names this specificatimlcomposition which is mostly made up in the form of a pellet is ignited by an electric current, it burns down so slowly that by its flame dynamite and other easily ignited explosives are ignited. But the slow burning characteristic is a great disadvantage, for, should the electric fuse become detached from the detonator, the pellet may burn out Without igniting the detonator and delayed explosions may occur. A further disadvantage of the fuse consists in this, that the fuse as such is ca pable of igniting CH and air mixtures.

The present invention overcomes these difficulties by making use of compositions having a more rapid combustion.

To this class of compositions belong the mono and polybasic lead salts of higher nitrated bodies, more particularly of nitro phenols with two or three nitro groups. Neutral salts of nitro bodies may also be used which will ignite suiiiciently readily. Since, when using such electric fuses, a premature ignition of explosives and an ignition of CH and air mixtures cannot occur, the safety of blasting operations in mines is increased.

The production of such salts is carried out in accordance With U. S. Patent No. 1,478,429 to W. Friederich, one of the co-inventors of the present fuse.

Having now particularly described and ascertained the nature of our said invention and in what manner the same is to be performed, We declare that What We claim is 1; In an electric fuse including a detonating composition, an ignition pellet comprising a lead salt of a nitro phenol selected from a group consisting of neutral monobasic and polybasic lead picrate, the same being adapted to ignite the detonator in said fuse.

2. In an electric fuse including a detonating composition, an ignition pellet consisting of neutral monobasic lead picrate adapted to ignite said composition. a

3. In an electric fuse including a detonatin composition, an ignition pellet consist VVILHELM ESCHBACH. WALTER FRIEDERICH. 

